chromatographic separation and tandem mass spectrometry (MS/MS). In this chapter we will discuss some of the newer scan modes available on modern instruments made possible by fast scanning and high-resolution with accurate mass measurement.

Grissa, D., Comte, B., Pétéra, M., Pujos-Guillot, E., Napoli, A., 2020. A hybrid and exploratory approach to knowledge discovery in metabolomic data. Discrete Applied Mathematics 273, 103-116.

http://www.sciencedirect.com/science/article/pii/S0166218X18306346 In this paper, we propose a hybrid and exploratory knowledge discovery approach for analyzing metabolomic complex data based on a combination of supervised classifiers, pattern mining and Formal Concept Analysis (FCA). The approach is based on three main operations, preprocessing, classification, and postprocessing. Classifiers are applied to datasets of the form individuals × features and produce sets of ranked features which are further analyzed. Pattern mining and FCA are used to provide a complementary analysis and support for visualization. A practical application of this framework is presented in the context of metabolomic data, where two interrelated problems are considered, discrimination and prediction of class membership. The dataset is characterized by a small set of individuals and a large set of features, in which predictive biomarkers of clinical outcomes should be identified. The problems of combining numerical and symbolic data mining methods, as well as discrimination and prediction, are detailed and discussed. Moreover, it appears that visualization based on FCA can be used both for guiding knowledge discovery and for interpretation by domain analysts.

Grozeva, N.G., Klein, F., Seewald, J.S., Sylva, S.P., 2020. Chemical and isotopic analyses of hydrocarbon-bearing fluid inclusions in olivine-rich rocks. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, 20180431.

https://doi.org/10.1098/rsta.2018.0431 We examined the mineralogical, chemical and isotopic compositions of secondary fluid inclusions in olivine- rich rocks from two active serpentinization systems: the Von Damm hydrothermal field (Mid-Cayman Rise) and the Zambales ophiolite (Philippines). Peridotite, troctolite and gabbroic rocks in these systems contain abundant CH -rich secondary inclusions in olivine, with less abundant inclusions in plagioclase and clinopyroxene. 4 Olivine-hosted secondary inclusions are chiefly composed of CH and minor H , in addition to secondary 4 2 minerals including serpentine, brucite, magnetite and carbonates. Secondary inclusions in plagioclase are dominated by CH with variable amounts of H and H O, while those in clinopyroxene contain only CH . We 4 2 2 4 determined hydrocarbon abundances and stable carbon isotope compositions by crushing whole rocks and analysing the released volatiles using isotope ratio monitoring - gas chromatography mass spectrometry. Bulk - 1 rock gas analyses yielded appreciable quantities of CH and C H in samples from Cayman (4 -313 nmol g 4 2 6 - 1 - 1 CH and 0.02 -0.99 nmol g C H ), with lesser amounts in samples from Zambales (2 -37 nmol g CH and 4 2 6 4 - 1 13 0.004 -0.082 nmol g C H ). Mafic and ultramafic rocks at Cayman exhibit δ C values of -16.7‰ to 2 6 CH4 13 13 -4.4‰ and δ C values of -20.3‰ to +0.7‰. Ultramafic rocks from Zambales exhibit δ C values of C2H6 CH4 13 -12.4‰ to -2.8‰ and δ C values of -1.2‰ to -0.9‰. Similarities in the carbon isotopic compositions of C2H6 CH and C H in plutonic rocks, Von Damm hydrothermal fluids, and Zambales gas seeps suggest that leaching 4 2 6 of fluid inclusions may provide a significant contribution of abiotic hydrocarbons to deep-sea vent fluids and ophiolite-hosted gas seeps. Isotopic compositions of CH and C H from a variety of hydrothermal fields hosted 4 2 6 in olivine-rich rocks that are similar to those in Von Damm vent fluids further support the idea that a significant portion of abiotic hydrocarbons in ultramafic-influenced vent fluids is derived from fluid inclusions.

Gunsch, M.J., Liu, J., Moffett, C.E., Sheesley, R.J., Wang, N., Zhang, Q., Watson, T.B., Pratt, K.A., 2020. Diesel soot and amine-containing organic sulfate aerosols in an Arctic oil field. Environmental Science &Technology 54, 92-101.

https://doi.org/10.1021/acs.est.9b04825